Hi
I'm not too keen on these over weathered jobs, especially when they start lifting paint and heavy rusting.
I bought a class 37/0 a few months back on Ebay which had been Beautifully weathered by someone called Making Tracks, he uesd to sell a lot of stuff on Ebay and was quite dear. I picked this particular loco up for around 50 quid, an absolute bargin, there are still some to be had on occasion you just have to be patient.
Cheers
Bob